Tiring truing machine



United States Patent Inventor John A. Luton 4335 Napier St., San Diego,California 921 10 Appi. No. 737,024 Filed June 14, 1968 Patented Oct.20, 1970 TlRlNG TRUING MACHINE 5 Claims, 5 Drawing Figs.

US. Cl 157/13 132% 21/08 Field of Search 157/1 3 References Cited UNITEDSTATES PATENTS 10/1956 Bullis 157/13 2,852,073 9/1958 Rawis 3,003,54510/1961 Peacock Primary ExaminerGranville Y. Custer, Jr. Attorney-Knoxand Knox ABSTRACT: The machine has a frame on which is a driven rollerfor rotational driving contact with a vehicle tire. A carriage slidablymounted on the frame carries a crossfeed tool support, the carriagebeing linked to the frame by an adjustahie radius rod to follow apredetermined arcuate path when the crossfeed is operated, so guidingthe tool in the desired path across the face of the rotating tire. Meansare provided for precise setting of the cutting tool and for controlledadjustments while the machine is in operation.

Patented Oct. 20, 1 970 INVENTOR. JOH N A. LUTON Patented Oct. 20, 19703,534,799

INVENTOR. JOHN A. LUTON Patented Oct. 20, 1970 Sheet 3 Fig.4

Fig. 5

INVENTOR. J O H N A. LUTON TIRING TRUING MACHINE BACKGROUND OF THEINVENTION The present invention relates to vehicle servicing equipmentand specifically to a tire-truing machine. In the usual operation oftire-truing, a template is used to guide the cutting SUMMARY OF THEINVENTION The tire-truing machine described herein does not require atemplate, but utilizes a tool carrier coupled to a radius rod to swingin a controlled arcuate path. The machine is built on a rigid framewhich can be moved into position under a vehicle wheel, still mounted onthe vehicle, the wheel being rotated by a driven roller in frictionalcontact with the tire and maintained at a controlled suitable speed forefficient cutting. Adjustment is provided for the length of the radius,the position of the center of radius relative to the wheel, thepositioning of the cutting tool and the depth of cut, and control of thefeed as the machine is operated. The machine is self-contained and alloperating controls are readily accessible from one operators position,at which there is a clear view of the cutting action.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation view of thecomplete machine;

FIG. 2 is a sectional view taken on line 2-2 of FIG. 1;

FIG. 3 is a top plan view of the machine;

FIG. 4 is an enlarged sectional view taken on line 4-4 of FIG. 3; and

FIG. 5 is a further enlarged sectional view taken on line 5-5 of FIG. 4.

Similar characters of reference indicate similar or identical elementsand portions throughout the specification and throughout the views ofthe drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT The machine has a rigid baseframe 10, comprising a pair of elongated side rails 12 fixed in spacedparallel relation between crossbeams I4 and 16 at opposite ends of theframe. For purposes of description the crossbeam 14 will be referred toas at the forward end and the crossbeam 16 at the rear end, in relationto the direction in which the operator will normally face. Anintermediate crossbeam 18 is secured between the rails a short distancerearwardly from crossbeam 14. To support the frame on the floor, feet 20are fitted below the ends of crossbeams I4 and the center of crossbeam16, the feet being of any suitable adjustable type for levelingpurposes. Alterna-- tively the machine could be mounted on casters withlocking means, the structure being well known.

Secured to the top of crossbeam 14 near the ends are two leaf springs 22extending rearwardly in parallel relation toward crossbeam -l8 andinclined upwardly, as by use of wedge blocks 24. On the upper ends ofsprings 22 are bearings 26, between which is journaled a drive roller28. To minimize obstructions in the working area, the motor 30 fordriving roller 28 is mounted at the rear end of frame on a bracket 32secured to an end of crossbeam 16, and is coupled to the roller by aflexible drive shaft 34.

Mounted on a frame 10 is a slide carriage 36 having a pair of slideblocks 38 which are slidable on rails 12 and are interconnected byspaced parallel guide bars 40 extending laterally across the frame abovethe side rails. Slidably mounted on guide bars 40 is a cross carriage42, the position of which is controlled by a lateral feed screw 44journalcd between slide blocks 38 and threaded through a portion of thecross carriage. One end of feed screw 44 is fitted with a hand wheel 46for manual operation of the cross carriage. On top of cross carriage 42are upright posts 48 supporting a pair of spaced parallel guide bars 50which are horizontally slidable longitudinally through the posts.Attached to guide bars 50 is a tool platform 52, in which is alongitudinal feed screw 54 extending between guide bars 50 and passingthrough a threaded post 56 on cross carriage 42. On the rear end of feedscrew 54 is a hand wheel 58 for manual adjustment of the tool platform.The basic two-axis screw feed mechanism for moving the cross carriageand tool platform is well known and specific structure may vary fromthat shown.

Fixed on the forward end of tool platform 52 is a socket member 60 witha clamp screw 62 to hold a tool post 64 in upright position in thesocket member. The tool post is shown as being square in cross section,but other noncircular configurations may be used to prevent the toolpost from turning. At the upper end the tool post 64 has a recessedshoulder 66 on which a cutting tool 68 is secured by a lock screw 70,the cutting end 72 of the tool extending forward of the platform. Whilevarious types of cutting tools may be used, it has been found that aconventional tire-grooving tool will perform satisfactorily.

Secured longitudinally between crossbeams I6 and I8 is a fixed tie bar74 on which is an adjustable pivot block 76. The pivot block comprises asleeve member 78 slidable on tie bar 74, with a lock screw 80 forlocking at any position on the tie bar, the sleeve member having aflange 82 to which a second sleeve member 84 is pivotally attached by avertical center pin 86. Sleeve member 84 has a lock screw 88 to secureone end of a radius bar 90, the other end of which is connected by apivot pin 92 to a lug 94 on the rear lower portion of cross carriage 42,as in FIGS. 4 and 5. The tie bar 74 is positioned slightly to one sideof the longitudinal center line of the frame 10, to allow the axis ofcenter pin 86 to fall on the center line forsymmetrical travel of thecarriage assembly. When hand wheel 46 is turned to rotate feed screw 44,the cross carriage 42 is moved laterally across the frame, but theradius bar causes the cross carriage to move in an arcuate path having aradius equal to the distance between the centers of pins 86 and 92. Toaccommodate the longitudinal displacement in the arcuate path, the slidecarriage 36 slides on rails 12. Thus only the hand wheel 46 need beoperated to move the carriage assembly through its preset path.

In use, the tire to be treated is left on the vehicle, which is jackedup so that the truing machine can be placed underneath. The vehicle isthen lowered so that the tire 96, indicated in broken line in FIG. I,rests on roller 28 with sufficient pressure for driving contact, theresiliency of springs 22 maintaining the contact. Pivot block 76 isadjusted to set the radius and center of radius for the required tireprofile, and the tool platform 52 is adjusted by means of hand wheel 58to bring the tool 68 into cutting position adjacent the tire. The depthof cut can be accurately set by means of hand wheel 58 and will be heldat that setting during the lateral motion across the tire. However, ifit is necessary to modify the arcuate contour slightly this is easilydone while the machine is in operation, the cutter and controls beingconveniently placed for access by the operator. With the feed screwcontrol, adjustments to the cutter can be predetermined as specificfractions of a turn of hand wheel 58 and are thus repeatable, withoutthe need for a template or special guide means.

By means of the adjustable pivot block 76 the apparatus can be set forany of the usual tire sizes, so that the cutting tool is properlypositioned when the tire is in driving position on the roller 28. Forvery small or very large tires a tool post 64 of suitable length wouldbe used to hold the cutting tool in the most effective cutting position.

It is understood that minor variation from the form of the inventiondisclosed herein may be made without departure from the spirit and scopeof the invention, and that the specification and drawings are to beconsidered as merely illustrative rather than limiting.

Iclaim:

l. A tire-truing machine, comprising:

an elongated, rigid base frame having a driven tire-engaging rollermounted thereon adjacent one end;

a carriage assembly slidably mounted on said frame for adjustmentlongitudinally of the frame and having-a portion (42) thereof separatelyslidablc transversely of the frame;

a tool holder secured to said portion of said carriage assembly andhaving a cutting tool thereon extending toward said roller;

said carriage assembly including feed means to move said portionrelative to the remainder of said assembly; and

a single radius bar (90) pivotally connected between said frame and saidportion only.

2. The structure of claim 1 and including a longitudinal tie bar (74)fixed in said frame, a pivot block (76) longitudinally adjustablysecured (80) to said tie bar and comprising the center of radius pivotconnection of said radius bar, the radius bar being adjustably secured(88) to said pivot block.

3. The structure of claim 1, wherein said frame has spaced parallel siderails, said carriage assembly including a slide carriage longitudinallyslidable on said rails and having transverse guide bar means (40), saidportion of the carriage assembly comprising a cross carriage laterallyslidably mounted on said guide bar means for movement across said slidecarriage 4. The structure of claim 3, wherein said radius bar isdirectly and pivotally connected to said cross carriage.

5. The structure of claim 3, and including a longitudinal tie bar fixedin said frame, a pivot block longitudinally adjustably secured to saidtie bar and comprising the center of radius pivot connection of one endof said radius bar, the other end of said radius bar being pivotallyconnected to said cross carriage.

